Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2015 |
Sep. 30, 2015 |
Jun. 30, 2015 |
Mar. 31, 2015 |
Dec. 31, 2014 |
Sep. 30, 2014 |
Jun. 30, 2014 |
Mar. 31, 2014 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Quarterly Financial Information Disclosure [Abstract] | |||||||||||
| Revenue | $ 427.6 | $ 404.1 | $ 417.7 | $ 450.7 | $ 425.6 | $ 408.2 | $ 410.1 | $ 420.0 | $ 1,700.1 | $ 1,663.9 | $ 1,777.5 |
| Operating income | 54.9 | 101.8 | 110.5 | 142.5 | 136.1 | 97.3 | 104.8 | 113.5 | 409.7 | 451.7 | 425.2 |
| Net income | 27.9 | 59.5 | 63.0 | 86.1 | 77.4 | 55.8 | 69.0 | 66.8 | |||
| Net income attributable to stockholders | $ 27.9 | $ 60.2 | $ 63.4 | $ 84.6 | $ 80.0 | $ 56.3 | $ 70.1 | $ 64.9 | $ 236.1 | $ 271.3 | $ 247.3 |
| Basic net income per common share | $ 0.27 | $ 0.59 | $ 0.63 | $ 0.84 | $ 0.78 | $ 0.54 | $ 0.66 | $ 0.60 | $ 2.33 | $ 2.57 | $ 2.13 |
| Diluted net income per common share | $ 0.26 | $ 0.57 | $ 0.59 | $ 0.80 | $ 0.74 | $ 0.51 | $ 0.62 | $ 0.56 | $ 2.22 | $ 2.43 | $ 2.04 |
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- References No definition available.
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- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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